Per the Marine Disaster Emergency Plan, the National Marine Forecasting Center
has issued the highest (red) wave alert. Typhoon No.18 Sader (strong typhoon) is
approaching the Zhejiang–Fujian coast and coincides with an astronomical high
tide. Northern Zhejiang and Fujian coasts may face compounded wind, rain, waves
and tide; storm surge superposed on the astronomical high tide risks seawater
backflow and flooding of low-lying coastal areas in Zhejiang.